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1192                          Appendix  VI.

hexagon end of the axle, so as to be easily unshipped. The
casing is prevented from rotation by the steadiment/ to frame w,
and h is the brake drum.

Pitch-chain drive is shewn at Fig. 975-6, and is also men

  a                         tioned on pp. 545 and 1003-5.    Slackness of chain, if consider-

* *                         able, is remedied by the withdrawal of one or more links : if less

important, by the adjustment in length of a screwed rod A,
Fig. 1052, which serves as a stay between the-chain shaft bracket
c and the hind axle B. A right- and left-hand nut alters the
length as required.

The Ackermann Steering Gear will be understood by reference
to p. 1003 and Fig. 919. The coupling rod 4 is connected to the
levers s s, which are splayed outward when the rod is in front,
but inward when behind the axle (see Fig. 1055). These levers
are again seen at HJ. Fig. 1052, and a third lever GX is coupled by
a rod F! to the lever EJ. , which is actuated by worm gear DX from
the hand wheel AX through pillar c^ The small levers B! are for
advance spark, mixture, &c.

Two brakes are provided, whose general relationship is shewn
at the head of Fig. 1053. The foot brake is usually placed on
the propeller shaft at A, but can also be put upon the chain shaft
at B, while a pair of emergency brakes EX EJ are supplied on the
hind axle. As brake straps (Fig. 590, p. 570) are non-reversible,
they have given way to blocks, and the foot- or shaft-brake is a
drum E, on the right, having two such blocks F F that are pressed
together by the pedal H and lever j, the release being effected by
the spring, and the torque being received on the abutment K on
the frame. The wheel brake also consists of a pair of blocks
FX FX all with renewable cast-iron shoes, placed within a drum
attached to the wheel spokes; and the brake is put in action by
the toggle lever AP which is pulled over by the steel cord Gx
attached to the hand lever, the upper stud BZ being meanwhile
held firmly to the frame by the rod c.

In order that the brake may be applied simultaneously to
both wheels, the hand lever is fixed to a shaft lying across the
frame, and the brake rods are connected to short levers also
keyed thereon. An exact compensation is obtained by the

i J                        Panhard steel cord ^, which passes through the brake shaft g and